She just couldn't sustain it in the second half for the No. 7 Blue Devils.

The team's leading scorer finished with 19 points in the 64-60 loss at No. 14 North Carolina on Sunday, though she managed just four points and one basket after halftime.

"I don't think they were helping off as much," Liston said. "But I'm sure I could've done some more things offensively and been a little more aggressive."

Liston had missed the past two days of practice due to her back, but hit a 3-pointer on the game's opening possession and went 5-for-7 from the field with 15 points in the opening half.

In the second half, however, Liston went 1-for-5 with only a layup at the 14:16 mark to end UNC's 20-0 run spanning halftime.

Being chased by UNC freshman Diamond DeShields, Liston didn't score again until hitting two free throws in the closing seconds with her team down two possessions.

"We were helping out a pretty good bit off of her and she was getting some open looks," UNC associate head coach Andrew Calder said of the first half. "And Diamond made the adjustments she needed to make with her high basketball IQ to shut her down."

For UNC, DeShields scored 18 points while fellow freshman Allisha Gray scored all 12 of her points after halftime.

Freshman Stephanie Mavunga had 12 points and 11 rebounds for the Tar Heels (22-8, 10-6 Atlantic Coast Conference), who clinched their first season sweep of the Blue Devils since the 2007-08 season.

North Carolina led by 19 points after its big run, then watched Duke (25-5, 12-4) respond with a 16-0 burst and fight back to within a point before holding on down the stretch.

Mavunga came up big, scoring on a stickback after Duke got within 53-52 on Ka'lia Johnson's three-point play. She then kicked out to Gray for a 3-pointer then scored inside off a feed from DeShields that pushed the lead back to 60-52 with 2:02 left.

The Tar Heels won the first meeting on Feb. 10, with DeShields scoring 30 in UNC's first win in Duke's famously hostile Cameron Indoor Stadium since 2008.

But the Tar Heels had lost two straight games coming into this one, losing at home on a cold-shooting day to a Virginia Tech team with two league wins followed by Thursday's 25-point loss at No. 2 Notre Dame.

DeShields didn't shoot particularly well, going just 7 for 22 from the field this time around. She set a freshman single-season scoring record in the first half.

But Gray, who was limited to eight first-half minutes when she picked up two fouls, hit four 3-pointers after halftime. Two of those sparked UNC's big run, with the Tar Heels scoring the first 14 points after halftime to take a 50-31 lead on DeShields' free throw with 16:11 left.

Yet the Blue Devils, who had been scoreless for 7 1/2 minutes during UNC's run, answered with an equally impressive burst of their own. That 16-0 spurt against the suddenly turnover-prone Tar Heels -- who at one point had turnovers on four straight possessions and went scoreless for 10 minutes -- helped them climb back in the game.